1. Field of the Invention
The present invention relates to the GIS field, and particularly to a method and apparatus for checking the correctness of GIS data.
2. Description of Related Art
GIS (Geographic Information System) data including geographic and demographic data have become more and more important, and have found more and more widespread application in fields such as market analysis applications, facility positioning, urban planning, etc. In most of such cases, a huge amount of GIS data (e.g., over 150,000 records for the city of Beijing) are a foundation to ensure the successes of these applications. However, so far there is no good technical method and tool which can check the huge amount of geographic and demographic data quickly and automatically.
The checking of geographic and demographic data is very important. For an end user, such as a bank or a retailer, data correctness is critical for the quality of quantitative analyses of its GIS system. Therefore, before conducting a quantitative analysis, given geographic and demographic data should be checked carefully to determine whether these data sets are sufficiently complete and correct, thus avoiding incorrect decisions being made based on them. For a vendor of GIS data, the checking of the correctness of the GIS data is one of the most important aspects for increasing its competitiveness and decreasing its labor costs.
Since geographic and demographic data are usually collected and purchased from various channels, such as public or governmental departments or GIS and demographic data vendors, and often belong to different periods, there may exist some incorrect, outdated or inaccurate data therein. However, it is a costly work to check each data source channel and it is very difficult to implement automatic checking of GIS data.
An existing method for checking GIS data is to select certain sampling points and verify the data of these sampling points manually in the field. This kind of method not only is time consuming, laborious and inefficient, but also has insufficient effectiveness and accuracy since the correctness of the data of a few sampling points can not well reflect the correctness of all the GIS data. In addition, this kind of manual checking method in the prior art can only check the GIS data in a city level or a large region level, and can not be used for a more granular checking. For example, if the data on certain sampling points are determined as incorrect, then the GIS data of a whole city or region will be determined as incorrect.
There is needed a technical solution capable of checking the correctness of GIS data more quickly and effectively in the art.